Various inventions have been made regarding technologies for providing information on the best exit for a vehicle leaving a large parking lot or facility having multiple exits.
For example, patent document 1 discloses a navigation device that selects an exit closest to the current position in linear distance or travel distance as the best exit or selects an exit having a traffic signal or a destination sign at an intersection with a road link as the best exit.
As another example, patent document 2 discloses a guidance method where guidance information including routes to exits of a parking lot is generated by a server and a vehicle in the parking lot is guided via wireless communications between an on-vehicle device and the server. In the disclosed method, respective exits are associated with roads (links) surrounding the parking lot and an exit associated with a link constituting a part of a route to a destination is selected.
[Patent document 1] Japanese Patent Application Publication No. 2002-168642
[Patent document 2] Japanese Patent Application Publication No. 2005-284699